Alkenes oxygenates

Exposure of the alkene to oxygen at ambient temperature and pressure produces an alkene-oxygen interpolymeric peroxide which explodes lightly on heating. An attempt to react the alkene with oxygen at 100 bar and 40-50°C caused a violent explosion in the autoclave. 

Aluminium tetrahydroborate, Alkenes, Oxygen Benzeneseleninic acid, Hydrazine derivatives Benzyltriethylammonium permanganate Bis(4-hydroxyphenyl) sulfone... 

Rhodium complexes were generally found to be more effective than iridium, but on the whole they show moderate activity in alkene oxygenation reactions. Significantly, epoxides, a typical product of the oxidation of olefins catalyzed by the middle transition metals, have rarely been evoked as products [18-22]. Although allylic alcohols [23] or ethers [24] have sometimes been described as products, the above cited rhodium and iridiiun complexes are characterized by an excellent selectivity in the oxygenation of terminal alkenes to methyl ketones. 

Garrone et al. (163) have rationalized all these results by proposing the following mechanism for the adsorption of hydrogen and alkenes. Oxygen ions in positions of low coordination on the surface abstract protons from the adsorbed molecules to form OH c ions and a carbanion ... 

Properties Colorless gas often bluish due to impurities m.w. 49.00 dens. 1.32 (liq.), 1.72 (solid) f.p. -132 C b.p. -60 C Toxicology Toxic by Inh. poison severe irritant to skin, eyes, and mucous membranes Precaution Vigorous reaction with glass corrosive to quartz explosive reaction with alkenes oxygen difluoride incandescent... 

It has so far been impc sible to evaluate the relative importance of these reactions in photooxidation. Finally, it was assumed (37) that the part of alfiorption due to the oxygen-perturbed S T excitation (B) that may be foimd in alkenes-oxygen system mi t start photooxidation according to the following two reactions (33) ... 

Quantitative M.O. models were used in a discussion of the photoelectron spectrum of thiiran 1,1-dioxide. As compared with dimethyl sulphone, all antibonding S—C cr-orbitals increase in energy and bonding S—C a-orbitals decrease in energy because of the relative compression of the S—C bonds in the cyclic sulphone. The chelotropic reactions of thiiran 1,1-dioxide have been compared with the formation of alkene-oxygen Tr-complexes. Activation parameters for the extrusion of sulphur dioxide from thiiran 1,1-dioxide have been obtained. ... 

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